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author | Greg Ungerer <gerg@uclinux.org> | 2011-03-22 13:39:27 +1000 |
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committer | Greg Ungerer <gerg@uclinux.org> | 2011-03-25 14:05:13 +1000 |
commit | 66d857b08b8c3ed5c72c361f863cce77d2a978d7 (patch) | |
tree | 47222d86f4d78dc0da31baf64188bd2e4b38ac1e /arch/m68k/platform/coldfire/pit.c | |
parent | d39dd11c3e6a7af5c20bfac40594db36cf270f42 (diff) | |
download | op-kernel-dev-66d857b08b8c3ed5c72c361f863cce77d2a978d7.zip op-kernel-dev-66d857b08b8c3ed5c72c361f863cce77d2a978d7.tar.gz |
m68k: merge m68k and m68knommu arch directories
There is a lot of common code that could be shared between the m68k
and m68knommu arch branches. It makes sense to merge the two branches
into a single directory structure so that we can more easily share
that common code.
This is a brute force merge, based on a script from Stephen King
<sfking@fdwdc.com>, which was originally written by Arnd Bergmann
<arnd@arndb.de>.
> The script was inspired by the script Sam Ravnborg used to merge the
> includes from m68knommu. For those files common to both arches but
> differing in content, the m68k version of the file is renamed to
> <file>_mm.<ext> and the m68knommu version of the file is moved into the
> corresponding m68k directory and renamed <file>_no.<ext> and a small
> wrapper file <file>.<ext> is used to select between the two version. Files
> that are common to both but don't differ are removed from the m68knommu
> tree and files and directories that are unique to the m68knommu tree are
> moved to the m68k tree. Finally, the arch/m68knommu tree is removed.
>
> To select between the the versions of the files, the wrapper uses
>
> #ifdef CONFIG_MMU
> #include <file>_mm.<ext>
> #else
> #include <file>_no.<ext>
> #endif
On top of this file merge I have done a simplistic merge of m68k and
m68knommu Kconfig, which primarily attempts to keep existing options and
menus in place. Other than a handful of options being moved it produces
identical .config outputs on m68k and m68knommu targets I tested it on.
With this in place there is now quite a bit of scope for merge cleanups
in future patches.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Diffstat (limited to 'arch/m68k/platform/coldfire/pit.c')
-rw-r--r-- | arch/m68k/platform/coldfire/pit.c | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/arch/m68k/platform/coldfire/pit.c b/arch/m68k/platform/coldfire/pit.c new file mode 100644 index 0000000..c2b9809 --- /dev/null +++ b/arch/m68k/platform/coldfire/pit.c @@ -0,0 +1,169 @@ +/***************************************************************************/ + +/* + * pit.c -- Freescale ColdFire PIT timer. Currently this type of + * hardware timer only exists in the Freescale ColdFire + * 5270/5271, 5282 and 5208 CPUs. No doubt newer ColdFire + * family members will probably use it too. + * + * Copyright (C) 1999-2008, Greg Ungerer (gerg@snapgear.com) + * Copyright (C) 2001-2004, SnapGear Inc. (www.snapgear.com) + */ + +/***************************************************************************/ + +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/param.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/clockchips.h> +#include <asm/machdep.h> +#include <asm/io.h> +#include <asm/coldfire.h> +#include <asm/mcfpit.h> +#include <asm/mcfsim.h> + +/***************************************************************************/ + +/* + * By default use timer1 as the system clock timer. + */ +#define FREQ ((MCF_CLK / 2) / 64) +#define TA(a) (MCFPIT_BASE1 + (a)) +#define PIT_CYCLES_PER_JIFFY (FREQ / HZ) + +static u32 pit_cnt; + +/* + * Initialize the PIT timer. + * + * This is also called after resume to bring the PIT into operation again. + */ + +static void init_cf_pit_timer(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + + __raw_writew(MCFPIT_PCSR_DISABLE, TA(MCFPIT_PCSR)); + __raw_writew(PIT_CYCLES_PER_JIFFY, TA(MCFPIT_PMR)); + __raw_writew(MCFPIT_PCSR_EN | MCFPIT_PCSR_PIE | \ + MCFPIT_PCSR_OVW | MCFPIT_PCSR_RLD | \ + MCFPIT_PCSR_CLK64, TA(MCFPIT_PCSR)); + break; + + case CLOCK_EVT_MODE_SHUTDOWN: + case CLOCK_EVT_MODE_UNUSED: + + __raw_writew(MCFPIT_PCSR_DISABLE, TA(MCFPIT_PCSR)); + break; + + case CLOCK_EVT_MODE_ONESHOT: + + __raw_writew(MCFPIT_PCSR_DISABLE, TA(MCFPIT_PCSR)); + __raw_writew(MCFPIT_PCSR_EN | MCFPIT_PCSR_PIE | \ + MCFPIT_PCSR_OVW | MCFPIT_PCSR_CLK64, \ + TA(MCFPIT_PCSR)); + break; + + case CLOCK_EVT_MODE_RESUME: + /* Nothing to do here */ + break; + } +} + +/* + * Program the next event in oneshot mode + * + * Delta is given in PIT ticks + */ +static int cf_pit_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + __raw_writew(delta, TA(MCFPIT_PMR)); + return 0; +} + +struct clock_event_device cf_pit_clockevent = { + .name = "pit", + .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, + .set_mode = init_cf_pit_timer, + .set_next_event = cf_pit_next_event, + .shift = 32, + .irq = MCFINT_VECBASE + MCFINT_PIT1, +}; + + + +/***************************************************************************/ + +static irqreturn_t pit_tick(int irq, void *dummy) +{ + struct clock_event_device *evt = &cf_pit_clockevent; + u16 pcsr; + + /* Reset the ColdFire timer */ + pcsr = __raw_readw(TA(MCFPIT_PCSR)); + __raw_writew(pcsr | MCFPIT_PCSR_PIF, TA(MCFPIT_PCSR)); + + pit_cnt += PIT_CYCLES_PER_JIFFY; + evt->event_handler(evt); + return IRQ_HANDLED; +} + +/***************************************************************************/ + +static struct irqaction pit_irq = { + .name = "timer", + .flags = IRQF_DISABLED | IRQF_TIMER, + .handler = pit_tick, +}; + +/***************************************************************************/ + +static cycle_t pit_read_clk(struct clocksource *cs) +{ + unsigned long flags; + u32 cycles; + u16 pcntr; + + local_irq_save(flags); + pcntr = __raw_readw(TA(MCFPIT_PCNTR)); + cycles = pit_cnt; + local_irq_restore(flags); + + return cycles + PIT_CYCLES_PER_JIFFY - pcntr; +} + +/***************************************************************************/ + +static struct clocksource pit_clk = { + .name = "pit", + .rating = 100, + .read = pit_read_clk, + .shift = 20, + .mask = CLOCKSOURCE_MASK(32), +}; + +/***************************************************************************/ + +void hw_timer_init(void) +{ + cf_pit_clockevent.cpumask = cpumask_of(smp_processor_id()); + cf_pit_clockevent.mult = div_sc(FREQ, NSEC_PER_SEC, 32); + cf_pit_clockevent.max_delta_ns = + clockevent_delta2ns(0xFFFF, &cf_pit_clockevent); + cf_pit_clockevent.min_delta_ns = + clockevent_delta2ns(0x3f, &cf_pit_clockevent); + clockevents_register_device(&cf_pit_clockevent); + + setup_irq(MCFINT_VECBASE + MCFINT_PIT1, &pit_irq); + + pit_clk.mult = clocksource_hz2mult(FREQ, pit_clk.shift); + clocksource_register(&pit_clk); +} + +/***************************************************************************/ |